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2.5
Hydrography
2.5.1
Tides
Gilberto Rodriguez
The tides in the outer Gulf of Venezuela, like in the rest of the Caribbean, are of the
mixed type in which the diurnal component predominate. The diurnal range of the
tide is 0.25 m. In the southern part of the Gulf the semidiurnal components are largely
amplified by near-resonance, resulting in semidiurnal mixed tides with a range of
0.80 m (Pelegrf and Avila 1986). As the tidal wave enters Tablazo Bay it is considerable
distorted by the dimensions of the bay, but retains its fundamental characteristics.
Along the Strait the inequalities between successive tides diminishes and in the northern part of the lake the tidal wave regains its diurnal mixed type.
The analysis of records from tidal gauges located on a line between Tablazo Bay
and the Strait (Rodriguez 1970) shows that tidal range diminishes progressively
throughout the estuary, from 1.10 m at the entrance of Tablazo Bay, to 0-40 m at the
city of Maracaibo. The curve of best fitting is an exponential of the form
A = Ne- kD ,
where A is the tidal range in cm at a given point, N is the value in cm of A where D = 0,
k is the damping coefficient in cm- I , and D is the distance from the first tide gauge in
cm. The values calculated for this equation are
This equation is valid also in the lake as well. Differences in tidal range along the
year are negligible. High water takes place in Maracaibo city approximately 1 h after
high tide at the mouth of the estuary, 35 km distant, the wave travelling very slowly at
the beginning (10 km in 40 min) (Febres 1966).
The tides in the Lake Maracaibo can be analysed according to the theory of
tides in narrow embayments (Redfield 1961), as the addition of a primary wave entering from the sea and a secondary wave formed by the reflection of the first wave
on a barrier in the southern-most end of the lake. These waves are present along
the system in different positions and out of phase. The elevation (<;:1) of the primary
wave is
<;:1 = A cos (st - kx) e- mx ,
and that of the reflected wave (<;:2)
<;:2 = A cos (st + kx) e- mx •
The elevation of the water surface is
2.5
Hydrography
2.5.1
Tides
Gilberto Rodriguez
The tides in the outer Gulf of Venezuela, like in the rest of the Caribbean, are of the
mixed type in which the diurnal component predominate. The diurnal range of the
tide is 0.25 m. In the southern part of the Gulf the semidiurnal components are largely
amplified by near-resonance, resulting in semidiurnal mixed tides with a range of
0.80 m (Pelegrf and Avila 1986). As the tidal wave enters Tablazo Bay it is considerable
distorted by the dimensions of the bay, but retains its fundamental characteristics.
Along the Strait the inequalities between successive tides diminishes and in the northern part of the lake the tidal wave regains its diurnal mixed type.
The analysis of records from tidal gauges located on a line between Tablazo Bay
and the Strait (Rodriguez 1970) shows that tidal range diminishes progressively
throughout the estuary, from 1.10 m at the entrance of Tablazo Bay, to 0-40 m at the
city of Maracaibo. The curve of best fitting is an exponential of the form
A = Ne- kD ,
where A is the tidal range in cm at a given point, N is the value in cm of A where D = 0,
k is the damping coefficient in cm- I , and D is the distance from the first tide gauge in
cm. The values calculated for this equation are
This equation is valid also in the lake as well. Differences in tidal range along the
year are negligible. High water takes place in Maracaibo city approximately 1 h after
high tide at the mouth of the estuary, 35 km distant, the wave travelling very slowly at
the beginning (10 km in 40 min) (Febres 1966).
The tides in the Lake Maracaibo can be analysed according to the theory of
tides in narrow embayments (Redfield 1961), as the addition of a primary wave entering from the sea and a secondary wave formed by the reflection of the first wave
on a barrier in the southern-most end of the lake. These waves are present along
the system in different positions and out of phase. The elevation (<;:1) of the primary
wave is
<;:1 = A cos (st - kx) e- mx ,
and that of the reflected wave (<;:2)
<;:2 = A cos (st + kx) e- mx •
The elevation of the water surface is